The courts which have jurisdiction or authority in Western Australia are the High Court of Australia, the Federal Court of Australia, the Supreme Court of Western Australia, the Family Court of Western Australia, the District Court of Western Australia, the Magistrates Court and the Children's Court.
Courts operate in a hierarchical system. This means that a court is bound by any decisions of a higher court.
In Western Australia, the hierarchy moves upwards from the Magistrates Court to the District Court and then to the Supreme Court. To go above the Supreme Court, a case must go to the High Court of Australia, the ultimate court from which there is no appeal. Appeals from this court may only proceed to the High Court if the High Court grants special leave to appeal. Decisions of the High Court of Australia are binding on all Australian courts.
The Supreme Court has jurisdiction (the authority) over all criminal matters, but generally exercises its jurisdiction only over the most serious matters, including murder, armed robbery and serious drug offences. The Supreme Court has unlimited jurisdiction in civil matters.
Parliament enacts laws, known as Acts, statutes or legislation. The courts' role is to interpret and apply the laws that Parliament has enacted. If there is no statute which covers a particular issue, then the law is derived from decisions made by courts. This body of decisions is called the "common law". Decisions of courts such as the High Court of Australia, the Federal Court, the Supreme Courts of other states and territories and our own Supreme Court all form part of the common law. In deciding what the law is or what it should be where there is no legislation and no higher decision, state courts will also have regard to decisions of courts in common law countries overseas, particularly England and Wales, Canada, the United States and New Zealand.